1. Field of Invention
The present invention relates to an electro-optical apparatus, an electronic device, a substrate for use in an electro-optical apparatus, a method of producing a substrate for use in an electro-optical apparatus, and a light shielding film. More particularly, the present invention relates to a structure of a light shielding film having excellent light shielding performance which is advantageous for use in a projection-type liquid crystal display.
2. Description of Related Art
FIG. 15 is a cross-sectional view illustrating an example of a liquid crystal device. This liquid crystal device is formed of two transparent substrates made of glass, quartz or the like and a liquid crystal sealed between the two substrates, wherein one of the two substrates is a thin film transistor (hereinafter referred to as “TFT”) array substrate 10, and the other substrate is an opposite substrate 20 disposed at an opposing location.
A plurality of pixel electrodes 9a and pixel switching TFTs 30 for controlling the respective pixel electrodes 9a are formed in the shape of a matrix on the TFT array substrate 10, and the source region id of each TFT 30 is electrically connected via a contact hole 5 to a data line 6a for supplying an image signal. The gate of each TFT 30 is electrically connected to a scanning line 3a so that scanning signals, in the form of pulses, are supplied over the scanning line 3a in accordance with predetermined timing. The pixel electrode 9a is electrically connected to the drain region 1e of the pixel switching TFT 30 via a contact hole 8, so that when the pixel switching TFT 30, serving as a switching element, is closed for a predetermined period of time, image signals supplied via the data line 6a are written into the pixel.
The image signals with particular signal levels are applied to a liquid crystal via the respective pixel electrodes 9a, and the image signals are retained between the pixel electrodes 9a and an opposite electrode 21 formed on the opposite substrate 20 over a predetermined period of time. In general, in order to prevent leakage of the image signals, a storage capacitor is added in parallel to liquid crystal capacitance formed between the pixel electrode 9a and the opposite electrode 21. Herein, the storage capacitor is formed using a capacitor line 3b, which is an interconnection line provided for formation of the storage capacitor. Furthermore, an alignment film 16 that is subjected to an alignment treatment, such as rubbing, is disposed on the pixel electrode 9a. 
As shown in FIG. 15, a first light shielding film 11a that is formed of WSi (tungsten silicide) is disposed at a location corresponding to each pixel switching TFT 30 on the surface of the TFT array substrate 10.
This first light shielding film 11a prevents light returning from the TFT array substrate 10 from being incident upon the channel region 1a′ or the LDD region 1b or 1c of the pixel switching TFT 30.
A first interlayer insulating film (insulator layer) 12 for electrically isolating the semiconductor layer 1a from the first light shielding film 11a is disposed between the first light shielding film 11a and the pixel switching TFT 30. A second interlayer insulating film 4 is formed on the TFT array substrate 10, such that the scanning lines 3a and the insulating layer 2 are also covered with the interlayer insulating film 4, wherein the interlayer insulating film 4 has a contact hole 5 formed therethrough so as to reach the heavily doped source region id, and also has a contact hole 8 formed therethrough so as to reach the heavily doped drain region 1e. Furthermore, a third interlayer insulating film 7, having a contact hole 8 for connection to the heavily doped drain region 1e, is formed on the data line 6a and the second interlayer insulating film 4.
In this liquid crystal device, a storage capacitor 70 is formed by extending the insulating thin film 2 from a location under the scanning line 3a so that the extended part of the insulating thin film 2 serves as a dielectric film, and extending the semiconductor film 1a so that the extended part of the semiconductor film 1a serves as a first storage capacitor electrode 1f, and furthermore employing, as a second storage capacitor electrode, a part of the capacitor line 3b at a location corresponding to the first storage capacitor electrode if and the dielectric film.
On the other hand, an opposite electrode (common electrode) 21 is disposed over the entire surface of the opposite substrate 20, and, furthermore, an alignment film 22 subjected to an alignment treatment, such as rubbing, is disposed on the opposite electrode 21. Furthermore, in each pixel on the opposite substrate 20, a second light shielding film 23 is disposed in an area other than the display area. The second light shielding film 23 is also referred to as a black matrix and serves to prevent light incident on the side of the opposite substrate 20 from intruding into the channel region 1a′, the source region 1b or 1d, or the drain region 1c or 1e of the semiconductor layer 1a of the pixel switching TFT 30.
A liquid crystal is sealed in a space between the TFT array substrate 10 and the opposite substrate 20, which are constructed in the above-described manner and disposed such that the pixel electrodes 9a and the opposite electrode 21 face each other, thereby forming a liquid crystal layer 50 therein.